1. Field of the Invention
The present invention relates to a printing apparatus, printing method, and program that use a recording medium such as an optical disk as a printing object to print information such as a title of data recorded on the recording medium on its surface.
2. Description of the Related Art
Conventionally, the applicant of the present application has proposed printing apparatuses that print the title of an optical disk such as a CD-R (Compact Disk-Recordable) on its surface, and sold them in Japan.
This printing apparatus includes a tray that supports a disk and a printer mechanism that performs printing to the disk supported by this tray. The tray is moved to the external section of the apparatus main body by an inject operation, and the printer mechanism performs thermal transfer printing to the stationary optical disk, which is supported on the tray placed at a predetermined position of the apparatus main body, using an ink ribbon by a thermal head that moves backwards and forwards.
The aforementioned printer mechanism can arrange a character string in a linear or arc shape within one rectangular range corresponding to an effective print width, which the thermal head has, and a distance where the thermal head moves to scan, thereby making it possible to perform printing onto the surface of the optical disk by one print operation.
When a user wishes to provide printing to a plurality of portions of the surface (label surface) of the optical disk by the aforementioned printer mechanism, he/she performs the inject operation to once push the tray out of the apparatus after the end of printing one portion. Next, the user rotates the optical disk on the tray by a desired angle manually to be repositioned such that an area different from the print area at the first printing operation is made to correspond to the position of the printer mechanism. Thereafter, the user must return the tray to the apparatus main body to perform printing to a different portion of the optical disk by the second printing operation of the printer mechanism.
In addition, in the label printing of the optical disk, a character string is arranged circularly or semi-circularly along the circumference of a circular hole of the optical disk and this is useful as an arrangement form of the character string corresponding to the shape of the disc-like optical disk, and such a print result is desirably obtained.
As mentioned above, the printing apparatus can print the character string in an arc shape along the circumference around the circular hole of the optical disk. However, since the size of the rectangular print range where printing can be performed by one printing operation is decided, the print length of the character string where the characters are arranged in an arc shape is limited and the number of characters that forms the character string is also limited. Here, in the aforementioned printing apparatus, the print length of the arc-shaped character string that can be printed by one printing operation is about ⅕ of the circumference of the optical disk. For this reason, when the print character size of the arc-shaped character string is relatively increased, only the arc-shaped character string with the small number of characters can be printed. While, when the number of characters of the arc-shaped character string is relatively increased, the print character size of the arc-shaped character string becomes small as compared with the size of the optical disk. In this way, a good-looking print cannot be obtained by only one printing operation.
Additionally, it is not impossible to dividedly print the character string in a circular or semi-circular shape a plurality of times by the aforementioned printing apparatus. Namely, the user divides the character string to be printed in a circular or semi-circular shape to a plurality of character strings, and rotates the optical disk on the tray by a predetermined angle manually to be rearranged every time when each divided character string is printed on the optical disk in an arc shape, thereafter the user may return the tray to the apparatus main body to repeat the printing operation by a predetermined number of times.
However, it is complicated for the user to perform such an operation. Moreover, it is actually difficult to perform such an operation that accurately rotates the optical disk on the tray by the predetermined angle manually to be rearranged for each of the plurality of printing operation times. When there is an error in a rotation angle, such problems occur that a large space is generated between the adjacent characters at a boundary between the previous print portion and the print portion this time; inversely the adjacent characters are overlapped to degrade print quality.
As the printing apparatus other than the above, Unexamined Japanese Patent Application KOKAI Publication No.H5-238005 describes another printing apparatus that performs title-printing on the optical disk. This printing apparatus moves a print head of an ink jet device in a radial direction on the optical disk as rotating the optical disk to perform printing onto the optical disk spirally.
Since this printing apparatus can perform printing to the entirety of the label of the optical disk, it is possible to realize the print form in which the character string is arranged in a circular or semi-circular shape around the circular hole of the optical disk. However, since the print head is moved in the radial direction on the optical disk as rotating the optical disk to perform printing onto the optical disk spirally, it is necessary to control both the rotation of the optical disk and movement of the print head, causing a problem in which the control is complicated.
Moreover, this printing apparatus is one that drives the print head extending in the radial direction of the optical disk to rotate the optical disk one time to perform printing. In this printing apparatus, the rotational speed to the position close to the center on the optical disk is different from the position far therefrom and moving speed to the print head is slow at the position close to the center of the optical disk, so that a print result with high density can be obtained. In contrast to this, moving speed to the print head is fast at the position far from the center, so that a print result with low density can be obtained. For this reason, it is necessary to perform a specific print control to equalize print density at the position in the radial direction of the optical disk, causing a defect that control becomes further complicated.